Wireless communications system, communications device and wireless network infrastructure

ABSTRACT

A method performed by a communications device, the method comprising allocating a fraction of the data for transmitting to a first infrastructure equipment using a first carrier frequency, allocating a remainder of the data for transmitting to a second infrastructure equipment using a second carrier frequency, transmitting the fraction of data using the first carrier frequency and the remainder of data using the second carrier frequency, determining an attribute associated with communicating the data from the communications device to the first infrastructure equipment using the first carrier frequency based upon signals received from the first infrastructure equipment, modifying the fraction based on at least the determined attribute, and transmitting the data using at least one of the first and second carrier frequencies according to the modified fraction.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is based on PCT filing PCT/EP2018/070888, filedAug. 1, 2018, which claims priority to EP 17185819.4, filed Aug. 10,2017, the entire contents of each are incorporated herein by reference.

BACKGROUND Field of Disclosure

The present disclosure relates to wireless communications systems,communications devices and wireless network infrastructure, which areconfigured to provide uplink communication of data from a communicationsdevice to a first infrastructure equipment on a first carrier frequencyand to a second infrastructure equipment on a second carrier frequencyand to apportion uplink data between the two uplink carrier frequencies.

The present application claims the Paris Convention priority of Europeanpatent application EP17185819.4, the contents of which are herebyincorporated by reference.

Description of Related Art

The “background” description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description which may nototherwise qualify as prior art at the time of filing, are neitherexpressly or impliedly admitted as prior art against the presentinvention.

Wireless telecommunications systems, such as those based on the 3GPPdefined Long Term Evolution (LTE) and Long Term Evolution Advance(LTE-A) architectures, are applicable to communications betweennetworked user devices such as mobile telephones, and more widely alsoto applications such as the Internet of Things. The networked devicesare supported by a telecommunications network comprising base stationsor infrastructure equipment of various configurations offering wirelessconnection coverage using radio signals over particular areas, known ascells, and the base stations are in turn supported by a core network.Transmission of data between these various entities is achieved by theuse of radio bearers.

Various techniques are known by which transmissions can be more reliablyreceived at an intended destination. These may allow, for example,mobile devices to communicate when located at a greater distance from ainfrastructure equipment than would otherwise be the case. However, itis recognised that it may not be technically or economically feasible toapply these techniques equally to both uplink and downlinkcommunications. Even taking into account an expected imbalance in therequirements for uplink and downlink communications in which, forexample, an amount of capacity required or requested for downlink datacommunications exceeds a capacity requested or required for uplink datacommunications, there may exist a challenge in providing sufficientuplink communications capacity. In particular it may be a challenge toprovide sufficient uplink communications capacity when carriersoperating at high frequencies, for example, in a range from 3 GHz to 100GHz are used, due to the high path loss incurred by signals transmittedat such frequencies. These carriers may operate in accordance with a newradio (NR) or a 5G radio access technology (RAT), the specifications forwhich are currently under development.

SUMMARY OF THE DISCLOSURE

According to one example embodiment of the present technique, there isprovided a method performed in a communications device for transmittingdata to one of a first and second infrastructure equipment, the firstand second infrastructure equipment forming a part of a wirelesscommunications network and providing resources for uplink communicationsby the communications device on different carrier frequencies. Themethod comprises allocating a fraction of the data for transmitting tothe first base station of the wireless communications network using afirst carrier frequency, allocating a remainder of the data fortransmitting to a second base station of the wireless communicationsnetwork using a second carrier frequency, the second carrier frequencydiffering from the first carrier frequency, transmitting the fraction ofdata using the first carrier frequency and the remainder of data usingthe second carrier frequency, determining an attribute associated withcommunicating the data from the communications device to the first basestation using the first carrier frequency based upon signals receivedfrom the first base station, modifying the fraction based on at leastthe determined attribute, and transmitting the data using at least oneof the first and second carrier frequencies according to the modifiedfraction.

The determined attribute may be based on acknowledgement informationreceived from the first base station or by measurements of signalsreceived from the first base station.

Accordingly, uplink data transmissions can be allocated for transmissionto either the first base station or the second base station.

Various further aspects and features of the present invention aredefined in the appended claims and include methods performed in thefirst and second infrastructure equipment, a communications device,infrastructure equipment, and a system.

The foregoing paragraphs have been provided by way of generalintroduction, and are not intended to limit the scope of the followingclaims. The described embodiments, together with further advantages,will be best understood by reference to the following detaileddescription taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings wherein likereference numerals designate identical or corresponding parts throughoutthe several views, and wherein:

FIG. 1 is a schematic block diagram illustrating an example of awireless telecommunication system;

FIG. 2 is a message sequence chart illustrating a process by which acommunications device transmits uplink data according to an embodimentof the present technique;

FIGS. 3, 4 and 5 are graphical representations illustrating a fraction(R) of uplink data which is allocated for transmission to a first basestation, as a function of a measure of a quality of an uplinkcommunications channel by which data is transmitted from acommunications device to the first base station according to embodimentsof the present technique;

FIG. 6 is a message sequence chart illustrating a process by which acommunications device obtains resources for transmitting on an uplinkcarrier frequency to a base station in accordance with the presenttechnique;

FIG. 7 is a message sequence chart illustrating a process by which acommunications device obtains resources for transmitting on two uplinkcarrier frequencies to two base stations in accordance with the presenttechnique.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 1 provides a schematic diagram illustrating some basicfunctionality of a wireless telecommunications system 100, some or allof which may operate in accordance with long term evolution (LTE)principles and which may be adapted to implement embodiments of thedisclosure as described further below. Various elements of FIG. 1 andtheir respective modes of operation when operating in accordance withLTE principles are well-known and defined in the relevant standardsadministered by the 3GPP® body, and also described in many books on thesubject, for example, Holma H. and Toskala A [4]. It will be appreciatedthat operational aspects of the telecommunications network which are notspecifically described below may be implemented in accordance with anyknown techniques, for example according to the relevant standards.

The wireless telecommunications system 100 comprises a wireless networkwhich includes a plurality of base stations 101, 102 connected to a corenetwork 109. Each of the base stations 101, 102 provides a coverage area(i.e. a cell) 107, 108 within which data can be communicated to and froma communications device 103 using radio signals transmitted and receivedvia a wireless access interface. Data is transmitted from thecommunications device 103 to the base stations 101, 102 within theirrespective coverage areas 107, 108 via a radio uplink and data istransmitted from the base stations 101, 102 to the communications device103 via a radio downlink.

Each of the base stations 101, 102 is configured to include atransmitter 110 for transmitting signals representing the data via anantenna (which may be a plurality of antennas) on the downlink via awireless access interface, provided by the wireless communicationsnetwork, to wireless communications devices, such as the wirelesscommunications device 103. Each of the base stations 101, 102 alsoincludes a receiver 112 for receiving signals via the wireless accessinterface representing the data transmitted from the wirelesscommunications devices on the uplink and a controller 114 forcontrolling the transmitter 110 and the receiver 112.

The core network 109 represents one or more core network infrastructureequipment which may be configured to route data to and from thecommunications device 103 via the respective base stations 101, 102 fromand to other fixed line or wireless communications networks which arerepresented generally as a cloud 115. The core network 109 providesfunctions such as authentication, mobility management, charging and soon.

As with the base stations 101, 102, the communications device 103 alsoincludes a transmitter 120 for transmitting signals representing data onthe uplink of the wireless access interface to the base stations 101,102 and a receiver 122 for receiving signals representing data on thedownlink via the wireless access interface. The transmitter 120 and thereceiver 122 are controlled by a controller 124. The controller 124 mayperform other functions such as forming other layers in a protocol stackin accordance with communications protocols for communicating data toand from the wireless communications network.

Within both the base stations 101, 102 and the UE 103, the transmitter110, 120 (or transmitter circuitry), the receiver 112, 122 (or receivercircuitry), and the controller 114, 124 (or controller circuitry) may beimplemented using hardware circuits and/or software configuredprocessors. For example, the controller 114, 124 may be, for example, amicroprocessor, a CPU, or a dedicated chipset, etc., configured to carryout instructions which are stored on a computer readable medium, such asa non-volatile memory. The processing steps described herein may becarried out by, for example, a microprocessor in conjunction with arandom access memory, operating according to instructions stored on acomputer readable medium. The base stations 101, 102 may comprise morethan one communications interface (and associated transmitter andreceiver circuitry), such as a wireless communications interface forcommunication with one or more communications devices and acommunications interface (which may be wired or wireless) forcommunication with one or more core network equipment.

The communication of the data may be made using radio resources of thewireless access interface that are licenced for exclusive use by theoperator of the network. These radio resources may include resources on,for example, three carrier frequencies F1, F2 and F3. In the networkshown in FIG. 1, the resources operating on the carrier frequency F1 areused for the uplink communications of the data from the communicationsdevice 103 to the first base station 101. The resources on the carrierfrequency F3 are used for the downlink communications of the data fromthe first base station 101 to the communications device 103 and theresources centred on the carrier frequency F2 may be used for the uplinkcommunication of the data from the communication device 103 to thesecond base station 102. In some examples the carrier frequencies F1 andF3 may be the same, in which case the uplink communications of the dataand the downlink communications of the data to and from the first basestation 101 may operate in a time division duplex (TDD) fashion.

Descriptions of transmissions or resources which are described as “on”,“using” or “associated with” a particular carrier frequency will bereadily understood as encompassing, for example, transmissions orresources using frequencies within a frequency range which ischaracterized by the carrier frequency. A frequency range may be said tobe characterized by a particular frequency because, for example, thefrequency is the centre frequency of the range, or because thefrequency, within the range, is that at which control, pilot orsynchronization signals are transmitted. In particular, for example,where frequency division multiple access (FDMA) techniques are used, thetransmissions or resources may not span the entire frequency range butmay use only a portion of a frequency range which is characterised bythe carrier frequency F1.

Similarly, references to “measurement”, “quality” or “attribute” and thelike associated with a carrier frequency may refer to a measurement, aquality or an attribute and the like of signals within the rangecharacterized by the carrier frequency. For example, “radio conditions”associated with a carrier frequency may refer to a path loss, a signalstrength or a signal quality associated with signals transmitted usingresources within a frequency range characterized by a carrier frequency,even if those resources do not include the carrier frequency.

Embodiments of the present technique are not limited to any particularradio access technologies, however in some embodiments, thecommunication of the data between the first base station 101 and thecommunications device 103 may operate according to a new radio (NR)radio access technology which may be specified by the 3GPP organizationand may be referred to as 5G, while the communication of the databetween the communications device 103 and the second base station 102may operate according to long term evolution (LTE) communicationstechniques and protocols. The NR radio access technology may provide forenhanced mobile broadband (eMBB), massive machine type communications(mMTC) and/or ultra reliable and low latency communications (URLLC).

Although FIG. 1 shows only the uplink communications of data from thecommunications device 103 to the second base station 102, in someembodiments bidirectional communications may occur between thecommunications device 103 and the second base station 102, and in someother embodiments only uplink communications may occur from thecommunications device 103 to the second base station 102 whilebidirectional communications may be provided by the second base station102 for other communications devices which are not shown in FIG. 1.

In yet further embodiments the second base station 102 may operate usingspectrum (i.e. a frequency range) which is used both for new radio (NR)transmissions and for transmissions which are sent according to LTEspecifications. In such scenarios uplink transmissions from thecommunications device 103 may be transmitted according to NR protocolsand techniques, while transmissions from other devices, not shown, whichare also sent using resources on the carrier frequency F2 may betransmitted according to an LTE protocol.

In yet further embodiments, the second base station 102 may operateaccording to the NR specifications at one frequency range, and accordingto the LTE specifications at a different frequency range.

As such, the base stations 101 and 102 may provide the functionality ofan LTE eNodeB (eNB) or a NR gNodeB (gNB), or may provide bothfunctionalities simultaneously. However, the embodiments describedherein are not limited to any particular radio access technology, andthroughout this description, the term “base station” is used to refer tothe infrastructure equipment or functionality which forms part of theradio access network portion of the wireless communications system 100,and which controls transmissions to and reception from wirelesscommunications devices, such as the communications device 103. eNBs andgNBs are thus examples of entities which fall within the scope of theterm “base station” or “infrastructure equipment”.

Similarly, the communications device 103 may operate according to one ormore radio access technologies, and may also be referred to as a userequipment (UE) or a mobile station (MS).

In order to provide enhanced downlink coverage by a base station, suchas the first base station 101, the downlink transmission of the data,for example using the carrier frequency F3, may be made using abeamforming technique. Beamforming in conventional networks is typicallyused for data transmitted to a specific communications device or to aplurality of communications devices which are located close together(relative to the size of the cell of the base station). According tosome beamforming techniques the communications device 103 may feed backbeamforming weights i.e. precoding weights to the first base station 101allowing the first base station 101 to select a suitable set ofprecoding weights to form a beam directed towards the communicationsdevice 103. This technique can provide enhanced coverage for aparticular communications device; that is, the path loss (arising fromphysical distance between the communications device 103 and the firstbase station 101 and media through which signals must pass) at which thedownlink communication of data can be performed reliably can besignificantly increased. Alternatively, the rate at which data may bereliably transmitted from the first base station 101 to thecommunications device 103 may be thereby increased.

However, due to design constraints in communications devices it may notbe feasible to use similar techniques for the uplink communications ofdata from the communications device 103 to the first base station 101.In particular, it may not be feasible to implement a sufficient numberof antenna elements at the communications device 103 in order to enableeffective beamforming for the uplink transmission of the data.

This may lead to a scenario where the communications range for thedownlink communication of data is significantly greater than thecommunications range for the uplink communication of data between agiven base station, such as the first base station 101, and a givencommunications device, such as the communications device 103.

In addition, if the carrier frequencies F1 and F3 are not the same (inwhich case communications between the communications device and thefirst base station 101 may be operating in a frequency division duplex(FDD) mode) and the frequency F1 is higher than the frequency F3, a pathloss affecting signals transmitted for the downlink communication of thedata may be higher than a path loss affecting signals transmitted forthe uplink communication of the data.

Other design constraints, such as cost, power supplies, batterytechnology, and physical form factor constraints, which apply todifferent extents to wireless network equipment and to wirelesscommunications devices may additionally or alternatively give rise to animbalance between the capacity for the downlink communication of dataand the uplink communication of data that is available in respect of agiven wireless communications device.

An imbalance between the uplink and downlink capacities or ranges maylead to a situation where, at a given location, the communicationsdevice 103 may be provided with sufficient downlink resources to meetits needs, but available uplink resources are insufficient to be able tocommunicate all of the uplink data to the first base station 101 at therequired rate.

In order to remedy this deficiency it has been proposed that additionaluplink resources may be provided by means of a further carrier, such asthe one using the carrier frequency F2, which would enable thecommunications device 103 to transmit uplink data to the second basestation 102. These additional resources may be referred to as asupplementary uplink (SUL).

The beamforming technique referred to above is typically most beneficialwhen used at carrier frequencies greater than approximately 3 GHz. Insome embodiments of the present technique, the carrier frequencies F1(and F3, if different) are approximately 3 GHz or higher. It is proposedthat the supplementary carrier operating at the frequency F2 would use amuch lower frequency. In some embodiments, for example, F2 may be around2 GHz or lower. However, the embodiments described herein are notlimited to such scenarios.

Embodiments of the present technique provide a method for allocating theuplink data to be transmitted by a given communications device, such asthe communications device 103, to either resources on an uplinkcommunications channel using the carrier frequency F1, by which theuplink data is transmitted to the first base station 101, or to uplinkresources on an uplink communications channel using the carrierfrequency F2 for transmission to the second base station 102. Thefraction, or portion, of data allocated to each of the carrierfrequencies may be determined based on radio conditions of the uplinkcommunications channel which is using the carrier frequency F1. Ingeneral, a greater portion of the data may be allocated to the uplinkchannel using the carrier frequency F2 (which may be a supplementaryuplink) when the radio conditions for the channel using the carrierfrequency F1 are worse.

In some embodiments the first and second base stations 101, 102co-operate to provide dual connectivity (DC) to the communicationsdevice 103. In this case communication resources such as those using thecarrier frequencies F1 and F2 may be used substantially simultaneouslyto provide the uplink communication of the data, which may be associatedwith a radio bearer, from the communications device 103 to the basestations 101, 102. The first base station 101 may be a master basestation and perform operations specified for a master base station, andthe second base station 102 may be a secondary base station and performoperations specified for a secondary base station. The radio bearer maybe split, so that a portion of the uplink data associated with the radiobearer is transmitted from the communications device 103 to the firstbase station 101, and the remainder of the uplink data associated withthe radio bearer is transmitted between the communications device 103and the second base station 102. Protocols operating within thecommunications device 103 and at the first and second base stations 101,102 may ensure that this “split bearer” operation is transparent tohigher protocol layers, by means of appropriate buffering, re-ordering,etc., as necessary to meet the expectations of the higher protocollayers.

Co-ordination of resource allocations by the master base station 101 andsecondary base station 102 may occur by means of a communications link104 between the two base stations 101, 102.

In a conventional dual connectivity operation, the uplink data is splitbetween the two communications channels according to a predeterminedratio, only if the rate of the uplink data load associated with theradio bearer exceeds a predetermined threshold; otherwise, all of theuplink data is sent to the master base station.

A radio bearer may be associated with a quality of service (QoS) flow oran S1 bearer, and the first base station 101 may maintain a mappingbetween the radio bearer and the QoS flow or the S1 bearer.

An example embodiment of the present technique is illustrated in FIG. 1in which the communications device 103 uses two data buffers 105, 106.The data buffer 105 is used to store data received from upper layers(such as an application layer) which is to be allocated for transmissionto the first base station 101, while the data buffer 106 is for thetemporary storage of data which is to be transmitted usingcommunications resources on the carrier frequency F2 to the second basestation 102. The buffers 105, 106 are illustrated and described in orderto illustrate the embodiments of the present technique, but as will beappreciated by the skilled person, alternative techniques may be usedwithin the scope of the embodiments.

Embodiments of the present technique therefore provide means for thecommunications device 103 to determine an appropriate portion of thedata, which may be for example data received from upper layers in theprotocol stack of the communications device 103 or data received fromanother device which is to be relayed by the communications device 103to the wireless communications network, which is to be communicated tothe first base station 101. One example is shown in FIG. 2.

FIG. 2 provides a message sequence chart in which data is communicatedbetween the communications device 103, the first base station 101 andthe second base station 102 in accordance with an embodiment of thepresent technique. The process starts with a message exchange 201 bywhich the communications device 103 establishes a new radio (NR)connection with the first base station 101. As part of this connectionestablishment the communications device 103 is allocated resources ofthe uplink using the carrier frequency F1.

Subsequently, in a message exchange 203 the communications device 103establishes an uplink connection with the second base station 102. Theestablishment of the connection may occur directly between thecommunications device 103 and the second base station 102 or may makeuse of signalling between the communications device 103 and the firstbase station 101 and further communications between the first basestation 101 and the second base station 102.

In either case, as a result of this connection establishment thecommunications device 103 is allocated resources for at least uplinkcommunication using the carrier frequency F2. In some embodiments thecommunications device 103 may be also allocated resources for downlinkcommunications with the second base station 102.

At step 205 the communications device 103 estimates the uplink radioconditions associated with transmissions on the carrier frequency F1,that is to say it assesses an attribute of the uplink transmissionswhich are sent from the communications device 103 to the first basestation 101.

In some embodiments, step 203 may occur only after step 205; that is,the communications device 103 may request an establishment of theconnection with the second base station 102 only if the uplink radioconditions applicable to transmissions from the communications device103 to the first base station 101 fulfil predetermined criteria. Anexample of such embodiments is described below with reference to FIG. 6.

The attribute may be a strength associated with the signals received bythe first base station 101, a quality of signals received by the firstbase station 101, or some other appropriate metric or estimate thereofwhich may reflect the capability of the communications channel by whichthe uplink communication of the data are sent from the communicationsdevice 103 to the first base station 101. Further aspects of theattribute are described below.

Based on the estimated conditions of the uplink communication channel bywhich data is communicated from the communications device 103 to thefirst base station 101, the communications device 103 determines afraction, R, of uplink data which is to be sent via the communicationslink operating on the carrier frequency F1 to the first base station101, where R is a fraction between zero and 1 (inclusive), and where theremainder of the uplink data is to be sent using uplink resourcesoperating on the carrier frequency F2 to the second base station 102.

In some embodiments, a modulation and/or an encoding scheme applied touplink data which is transmitted at the carrier frequency F1 is adjustedbased on radio conditions for the carrier frequency F1. For example, arobust modulation and/or encoding scheme is used when channel conditionsare relatively low, such as, for example, when an attribute of theconditions of the channel using carrier frequency F1 is below apredetermined threshold. A relatively less robust modulation and/orencoding scheme may be used when channel conditions are relatively high.

Having determined the fraction R, then at steps 207 and 209 thecommunications device 103 transmits uplink data in accordance with thefraction determined as a result of step 205. That is to say, a fractionR of the data is sent to the first base station 101 using resources atthe carrier frequency F1, and the remainder of the data is sent to thesecond base station 102 using resources at the carrier frequency F2.

This process may repeat periodically. That is to say, steps 205, 207 and209 may repeat, for example, for the duration of the connection, and assuch the fraction R may be modified in order to reflect changes in thequality of the uplink communications channel between the communicationsdevice 103 and the first base station 101. Alternatively the fraction Rmay be modified in response to a detected change in the quality of theuplink communications channel; for example, R may be revised wheneverthe estimated channel conditions change and cross a particularthreshold.

FIGS. 3, 4 and 5 provide graphical representations illustrating methodsof determining the fraction R based on the uplink radio conditionsapplicable to communications sent on the uplink link from thecommunications device 103 to the first base station 101.

In FIGS. 3, 4 and 5, the vertical axis indicates the fraction R(expressed as a percentage from 0% to 100%) where R represents thefraction of uplink data which is assigned to be transmitted on theuplink carrier using the carrier frequency F1 to the base station 101.The remainder of the data, that is (100−R) (%), is allocated fortransmission on the supplementary uplink carrier frequency F2 to thesecond base station 102.

In FIGS. 3, 4 and 5, the horizontal axis represents an uplink radiocondition applicable to communications on the carrier frequency F1, withthe radio conditions progressively improving (e.g. increasing inquality) towards the right of the graph. For example, if the uplinkradio conditions are measured using a signal strength metric then thesignal strength increases from left to right.

In some embodiments, the communications device 103 receives anindication from the first base station 101 indicating an attributeassociated with the carrier frequency used for the uplink communicationof the data. That is, the first base station 101 may measure anattribute of the signals received from the communications device 103,and transmit an indication of the attribute to the communications device103.

In some embodiments, the attribute may be based on a bit error rate or ablock error rate based on acknowledgement information received from thefirst base station 101 in respect of data which has been transmitted bythe communications device 103 to the first base station 101. This maybe, for example, based on a hybrid automatic repeat request (HARQ)protocol feedback, or on a packet data convergence protocol (PDCP)status report. Alternatively or additionally, feedback from otherprotocol layers may be used.

In some embodiments, the attribute may be based on measurements ofdownlink signals received by the communications device 103 from thefirst base station 101 on the carrier frequency F3. For example, thecommunications device 103 may measure the signal strength of thedownlink transmissions which it receives from the first base station 101and, based on these measurements, may estimate a path loss or signalstrength metric associated with the uplink communications channel on thecarrier frequency F1. The communications device 103 may furtherdetermine a gain that applies to transmissions on the carrier frequencyF3 as a result of beamforming that is used for those transmissions fromthe first base station 101, and may use the determined gain to estimatethe uplink channel conditions.

In some embodiments, different metrics may be used depending on theduplex mode of operation of the communications with the first basestation 101. For example, in a time division duplex mode of operation,where F1 and F3 are the same frequency, an estimation of the uplinkchannel conditions may be obtained based on measurements of downlinktransmissions. In a frequency division duplex mode of operation, wherethe carrier frequencies F1 and F3 are different, the uplink channelconditions may be obtained by means of measurement feedback from thefirst base station 101.

In some embodiments the fraction R is determined directly based onmeasured attributes of signals received from the first base station 101on the carrier frequency F2 instead of an estimation or indication of ametric associated with uplink transmissions. For example, thecommunications device 103 may measure one or both of a reference signalreceived power (RSRP) and a reference signal received quality (RSRQ) ofsignals transmitted by the first base station 101 on the carrierfrequency F3. In such embodiments, the horizontal axis of FIGS. 3, 4 and5 represents a metric associated with downlink transmissions from thefirst base station 101 to the communications device 103 (improvingchannel from left to right). For the remainder of the description, it isassumed that R or other process steps are based on measurements of or anestimate of the uplink channel conditions on the carrier frequency F1for conciseness; however, the reader should understand that this doesnot preclude the use of a downlink channel metric instead of, orcombined with, an uplink channel metric in some embodiments.

FIG. 3 provides a graphical representation illustrating a method ofdetermining the fraction R in accordance with embodiments of the presenttechnique. In FIG. 3, at very poor uplink radio conditions on thecarrier frequency F1 (i.e. at the left-hand edge of the graph) none ofthe uplink data is transmitted on the carrier frequency F1 and this isillustrated at region 301. When the uplink radio conditions applicableto uplink communications on the carrier frequency F1 are very good, thenall of the uplink data is sent on the carrier frequency F1 and this isillustrated by the portion 303 in FIG. 3. For intermediate radioconditions, for example those between thresholds T1 and T2 on FIG. 3, anincreasing fraction of data is sent on the carrier frequency F1 as theuplink radio conditions on the carrier frequency F1 improve. This isillustrated by portion 302 of FIG. 3. In the embodiment illustrated inFIG. 3 the relationship between R and the uplink radio conditions on thecarrier frequency F1 between the thresholds T1 and T2 is shown as alinear relationship, however in other embodiments differentrelationships may exist. These may be non-linear or any otherappropriate function that is non-decreasing as a function of the uplinkradio conditions.

In some embodiments where the uplink radio conditions on the carrierfrequency F1 are sufficiently good, such as above a threshold T2, thesupplementary uplink (which may comprise a connection providingresources on the carrier frequency F2) may not be established at all,and in such embodiments the supplementary uplink may be initiated (forexample, a connection providing resources at the carrier frequency F2 isestablished) only in response to the uplink radio conditions on thecarrier frequency F1 falling below a predetermined threshold. This maybe the threshold T2 or may be some other threshold.

FIG. 4 provides a graphical representation illustrating an alternativemapping from the uplink radio conditions on the carrier frequency F1 tothe fraction R. In these embodiments, data is switched entirely from theuplink communications resources on the carrier frequency F1 to theuplink carrier resources on the carrier frequency F2 when the uplinkradio conditions applicable to transmissions on the carrier frequency F1fall below a certain threshold T3. In such embodiments, in order toavoid ping pong between the carrier frequencies F1 and F2, hysteresismay be applicable, that is to say data may be switched from the carrierfrequency F1 to the carrier frequency F2 when the radio conditions fallbelow a first predetermined threshold which may be the threshold T3.However, if the uplink radio conditions on the carrier frequency F1subsequently improve, then transmissions may be switched back to thecarrier frequency F1 only when the uplink radio conditions metricexceeds a threshold such as T4 (which may be the same as, or greaterthan T3).

Additionally, or alternatively, a time hysteresis may be applied inwhich case switching between carriers may be limited to only take placeno sooner than a certain predetermined time after the most recent switchhas occurred. Additionally, or alternatively, the switching betweencarriers may occur only when the radio conditions metric has exceeded(or fallen below) the appropriate threshold for a predetermined timeperiod.

FIG. 5 provides a graphical representation illustrating a principleaccording to which the fraction R may be determined, which is applicableto certain embodiments of the present technique. According to certainembodiments the rate at which data is offloaded from the resources usingthe carrier frequency F1 to the resources using the carrier frequency F2varies based on the available resources on the carrier frequency F2.Additionally, or alternatively, this variation may be based on the loadof (that is, the amount of data transiting through) the second basestation 102.

Starting from the right hand side of FIG. 5, at high quality uplinkconditions on the carrier frequency F1, all of the data is sent on thecarrier frequency F1, and R is equal to 100%. As conditions on thecarrier frequency F1 deteriorate then at some point (for example, whenan attribute associated with the carrier frequency F1 falls below athreshold T5 504) data is offloaded to the carrier frequency F2 and thefraction R accordingly decreases as the conditions associated with thecarrier frequency F1 progressively deteriorate. However, the rate atwhich data is offloaded varies according to the available resources onthe carrier frequency F2, as indicated by the arrow 505 which indicatesprogressively increasing resource availability on the carrier frequencyF2. In the case where there is a relatively small amount of data usingthe carrier frequency F2 then data may be offloaded very rapidly to thecarrier frequency F2, such that R decreases very quickly as the uplinkradio conditions of the channel operating at the carrier frequency F1deteriorate. This is shown in segment 501. On the other hand, if thereare only limited resources available on the carrier frequency F2, thenthe rate at which R decreases as a function of the uplink radioconditions on the carrier frequency F1 may be much lower, as shown insegments 502 and 503. Again, in FIG. 5 the relationship between R andthe uplink radio conditions on the carrier frequency F1 is shown asbeing linear on segments 501, 502 and 503. However, embodiments of thepresent technique are not limited to such linear relationships and anyother appropriate relationship may be used.

The available resources on the carrier frequency F2 may be reduced as aresult of other uplink and/or downlink data which is using the sameresources to or from other communications devices; this data may be sentaccording to the same, or a different RAT than the one used for theuplink communications sent from the communications device 103.

Thresholds, such as T1 and T2, may be predetermined (e.g. specified in astandard) or may be configured by the wireless network. For example, oneor both of the thresholds T1 and T2 may be configured by means ofsignalling as part of the establishment of the connection with the firstbase station 101 or transmitted by the first base station 101 as part ofbroadcast system information. In some embodiments of the presenttechnique, the thresholds may be implementation-dependent and configuredwithin the communications device 103.

According to the example embodiments explained above, the communicationsdevice 103 receives an indication from either or both of the first andsecond base stations 101, 102 providing one or more network parameterswhich the communications device 103 uses, together with the estimateduplink radio conditions on the carrier frequency F1, to determine thefraction R. One or more of the network parameters may reflect a load oravailable resources applicable to the uplink carrier frequency F2. Assuch, in some embodiments the rate at which data is offloaded from thecarrier frequency F1 to the carrier frequency F2 (which may becorrespond to a slope of the lines in FIG. 5) is dependent on theavailable uplink resources on the carrier frequency F2.

According to yet another aspect of the present technique thecommunications device 103 may determine when to request establishment ofthe communications link providing uplink resources on the carrierfrequency F2, and this may be based on an estimation of the uplink radioconditions applicable to transmissions on the uplink carrier frequencyF1 to the first base station 101. This embodiment may be particularlybeneficial when the communications device 103 has not recentlytransmitted on the carrier frequency F1 and therefore the first basestation 101 may not be able to determine when to initiate a request tothe second base station 102 to provide uplink resources (as illustrated,for example, in FIG. 7 and as described below).

FIG. 6 is a message sequence chart illustrating an exchange ofsignalling in accordance with some embodiments of the present technique.These embodiments provide benefits where, possibly as a result of theimbalance between uplink and downlink channel described above, thecommunications device 103 may not be able to reliably communicate arequest for additional uplink resources to the first base station 101.

According to these example embodiments, the communications device 103first establishes a connection which may be a new radio (NR) connectionwith the first base station 101 and thereby obtains uplink resourcesusing the carrier frequency F1. This is illustrated at step 601 of FIG.6.

Subsequently, the communications device 103 estimates the uplink radioconditions applicable to the uplink data transmissions using theseallocated resources on the carrier frequency F1 at step 603. Based onthe estimated uplink radio conditions on the carrier frequency F1 havingmet certain predetermined conditions, the communications device 103requests from the second base station 102 uplink resources at step 605.This may be, for example, in the form of a scheduling request (SR)transmitted directly to the second base station 102. The request may betransmitted on the carrier frequency F2. In some embodiments, thisrequest may be in the form of a connection request. The request mayconform to the same protocols and specifications as used for theconnection with the first base station, or may use a different protocol.

If the uplink transmissions on the carrier frequency F2 are sentaccording to LTE techniques, then the request may be sent on a channelsuch as a physical random access channel (PRACH), a physical uplinkshared channel (PUSCH) or a physical uplink control channel (PUCCH). Ifthe uplink transmissions on the carrier frequency F2 are sent accordingto NR techniques, then the request may be sent on resources on a PUCCHwhich are reserved for such requests. Alternatively, a grant-free PUSCHresource may be used to send the request.

In some embodiments the second base station 102 does not have downlinkconnectivity with the communications device 103. In these situations thesecond base station 102 may transmit an indication of an uplink grantcomprising uplink resources on the carrier frequency F2 to the firstbase station 101, for example by means of the communications link 104which connects the first and second base stations 101, 102. The firstbase station 101 then forwards this uplink grant to the communicationsdevice 103.

In other embodiments the second base station 102 is able to communicatedirectly with the communications device 103, in which case the uplinkgrant of uplink resources using the carrier frequency F2 is transmitteddirectly to the communications device 103. In either case the uplinkresources using the carrier frequency F2 are allocated to thecommunications device 103 and the communications device 103 isthereafter able to apportion data between the carrier frequency F1 andthe carrier frequency F2 based on an estimation of the uplink radioconditions on the carrier frequency F1.

FIG. 7 illustrates a message sequence chart illustrating a process bywhich the communications device 103 obtains resources for transmittingon the uplink carrier frequencies F1 and F2 to the first and second basestations 101, 102 in accordance with embodiments of the presenttechnique in which the uplink radio quality of the uplink channel usingthe carrier frequency F1 may be evaluated by the first base station 101.

In FIG. 7, at 701 uplink data is communicated from the communicationsdevice 103 to the first base station 101 using uplink resources on thecarrier frequency F1. Based on these uplink data transmissions the firstbase station 101 calculates at 703 the uplink radio quality based on anappropriate metric indicative of the ability of the uplinkcommunications link on the carrier frequency F1 to support uplink datacommunications from the communications device 103.

At step 705 the first base station 101 transmits an indication of theuplink radio quality on the carrier frequency F1 to the second basestation 102 using the communications link 104. Based on at least theindicated uplink radio quality on the carrier frequency F1 the secondbase station 102 allocates uplink resources for the communicationsdevice 103 on the carrier frequency F2 and transmits this resourceallocation to the first base station 101 at step 707. The first basestation 101 then transmits a resource allocation comprising resources onthe carrier frequency F2 based on the indication received from thesecond base station 102 and a resource allocation comprising resourceson the carrier frequency F1 to the communications device 103 as shown intransmissions 709 and 711. Based on these resource allocations thecommunications device 103 then transmits uplink data on the carrierfrequencies F1 and F2 as shown at 713. In these embodiments the fractionR, that is the portion of uplink data coming from the communicationsdevice 103 to the wireless communications network which is transmittedto the first base station 101, may be determined by the first basestation 101, for example in response to the assessment of the radioquality of the carrier frequency F1 performed at 703 and in response tothe uplink resource allocation received at 707. In some embodiments (notillustrated), the first base station 101 may request resourceallocations from the second base station 102 based on the determinedfraction R.

Alternatively the fraction R may be determined by the second basestation 102 in response to the receipt of the indication of the uplinkradio quality on the carrier frequency F1 which is received at 705. Thecalculated value of R may thus be communicated explicitly to thecommunications device 103 (e.g. together with a resource allocation) ormay be communicated implicitly (i.e. based on the resource allocationsfor the carrier frequencies F1 and F2). In embodiments where thefraction R is determined by one of the first and second base stations101, 102, a determination by the communications device 103 of anattribute associated with the uplink communication of the data to thefirst base station 101 may not occur.

Numerous modifications and variations of the present disclosure arepossible in light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims, the disclosuremay be practiced otherwise than as specifically described herein.

As will be appreciated by the skilled person, various combinations ofthe embodiments described above are possible, and features which aredescribed in the context of a particular embodiment may be applied toother described embodiments.

For example, the fraction R may be determined by the first base station101 based on a combination of an indication of a load associated withthe second base station 102 and measurements of signals transmitted bythe communications device 103, and may communicate the determined valueof R to the communications device 103, the second base station 102,both, or neither.

In another example, the attribute associated with the uplinkcommunications on the first carrier frequency F1 may be measured orestimated by means of acknowledgement information which is received in atime division duplex fashion on the first carrier frequency F1 and whichrelates to the uplink communications.

Various further example embodiments and features are defined in thefollowing numbered paragraphs:

Paragraph 1. A method for transmitting data by a communications devicein a wireless communications network, the method comprising:

-   -   allocating a fraction of the data for transmitting to a first        infrastructure equipment of the wireless communications network        using a first carrier frequency,    -   allocating a remainder of the data for transmitting to a second        infrastructure equipment of the wireless communications network        different from the first infrastructure equipment using a second        carrier frequency, the second carrier frequency differing from        the first carrier frequency,    -   transmitting the fraction of data using the first carrier        frequency and the remainder of data using the second carrier        frequency,    -   determining an attribute associated with communicating the data        from the communications device to the first infrastructure        equipment using the first carrier frequency based upon signals        received from the first infrastructure equipment,    -   modifying the fraction based on at least the determined        attribute, and    -   transmitting the data using at least one of the first and second        carrier frequencies according to the modified fraction.

Paragraph 2. A method according to Paragraph 1, the method comprising:

-   -   establishing a first connection providing uplink communications        using one or more channels operating at the first carrier        frequency with the first infrastructure equipment, monitoring        the determined attribute associated with communicating the data,    -   in response to the determined attribute satisfying predetermined        conditions, requesting an establishment of a second connection        for transmitting the data, and    -   receiving an allocation of resources using one or more channels        operating at the second carrier frequency for transmitting the        data to the second infrastructure equipment.

Paragraph 3. A method according to any of Paragraphs 1 to 2, comprising

-   -   receiving, from one of the first infrastructure equipment and        the second infrastructure equipment an indication of a network        parameter, wherein the modifying the fraction based on at least        the determined attribute includes    -   modifying the fraction based on a combination of the determined        attribute and the received network parameter.

Paragraph 4. A method according to Paragraph 3, wherein the networkparameter is based on a load of the second infrastructure equipment.

Paragraph 5. A method according to any of Paragraphs 1 to 4, wherein thedetermining an attribute associated with communicating the data from thecommunications device using the first carrier frequency includesreceiving an indication of a parameter associated with communicating thedata from the communications device using the first carrier frequencyfrom the first infrastructure equipment.

Paragraph 6. A method according to Paragraph 5, wherein the parametercomprises at least one of a path loss, an error rate, a received signalstrength and a received signal quality.

Paragraph 7. A method according to any of Paragraphs 2 to 4, wherein thefirst connection is a time division duplex connection providing uplinkand downlink communications using the first carrier frequency, and

-   -   the determining an attribute associated with communicating the        data from the communications device to the first infrastructure        equipment using the first carrier frequency based upon signals        received from the first infrastructure equipment includes    -   measuring at least one of a signal strength and a signal quality        of signals received from the first infrastructure equipment.

Paragraph 8. A method according to Paragraph 7, wherein the signalsreceived from the first infrastructure equipment for measuring at leastone of the signal strength and the signal quality include signalsrepresenting an acknowledgement information in respect of the datacommunicated from the communications device to the first infrastructureequipment using the first carrier frequency.

Paragraph 9. A method according to any of Paragraphs 2 to 6, wherein thefirst connection is a frequency division duplex connection providingdownlink communications at a third carrier frequency,

-   -   the signals received from the first infrastructure equipment        include acknowledgement information in respect of the data        communicated from the communications device to the first        infrastructure equipment using the first carrier frequency, and    -   the determining an attribute associated with communicating the        data from the communications device to the first infrastructure        equipment using the first carrier frequency based upon signals        received from the first infrastructure equipment includes    -   determining the attribute based on the received acknowledgement        information.

Paragraph 10. A method according to any of Paragraphs 1 to 9, wherein apath loss associated with the communicating the data from thecommunications device to the first infrastructure equipment using thefirst carrier frequency data exceeds a path loss for the signalsreceived from the first infrastructure equipment.

Paragraph 11. A method according to Paragraph 10, wherein a beamformingtechnique is applied by the first infrastructure equipment to thesignals received from the first infrastructure equipment.

Paragraph 12. A method according to any of Paragraphs 1 to 11, whereinthe first carrier frequency is greater than 3 GHz.

Paragraph 13. A method according to any of Paragraphs 1 to 12, whereinthe second carrier frequency is less than 2 GHz.

Paragraph 14. A communications device for transmitting data in awireless communications network, the communications device comprising:

-   -   transmitter circuitry, receiver circuitry and control circuitry,        wherein the control circuitry is configured    -   to allocate a fraction of the data for transmitting to a first        infrastructure equipment of the wireless communications network        using a first carrier frequency,    -   to allocate a remainder of the data for transmitting to a second        infrastructure equipment of the wireless communications network        different from the first infrastructure equipment using a second        carrier frequency, the second carrier frequency differing from        the first carrier frequency,    -   and to control the transmitter circuitry and the receiver        circuitry    -   to transmit the fraction of data using the first carrier        frequency and the remainder of data using the second carrier        frequency,    -   to determine an attribute associated with communicating the data        from the communications device to the first infrastructure        equipment using the first carrier frequency based upon signals        received from the first infrastructure equipment,    -   to modify the fraction based on at least the determined        attribute, and    -   to transmit the data using at least one of the first and second        carrier frequencies according to the modified fraction.

Paragraph 15. A communications device according to Paragraph 14, whereinthe control circuitry is configured with the transmitter circuitry andthe receiver circuitry

-   -   to establish a first connection providing uplink communications        using one or more channels operating at the first carrier        frequency with the first infrastructure equipment,    -   to monitor the determined attribute associated with        communicating the data,    -   in response to the determined attribute satisfying predetermined        conditions, to request an establishment of a second connection        for transmitting the data, and    -   to receive an allocation of resources using one or more channels        operating at the second carrier frequency for transmitting the        data to the second infrastructure equipment.

Paragraph 16. A communications device according to Paragraph 14 orParagraph 15, wherein the control circuitry is configured with thetransmitter circuitry and the receiver circuitry

-   -   to receive, from one of the first infrastructure equipment and        the second infrastructure equipment an indication of a network        parameter, and    -   to modify the fraction based on a combination of the determined        attribute and the received network parameter.

Paragraph 17. A communications device according to Paragraph 16, whereinthe network parameter is based on a load of the second infrastructureequipment.

Paragraph 18. A communications device according to any of Paragraphs 14to 17, wherein the control circuitry is configured with the transmittercircuitry and the receiver circuitry

-   -   to receive an indication of a parameter associated with        communicating the data from the communications device using the        first carrier frequency from the first infrastructure equipment,        and    -   to determine the attribute based on the parameter.

Paragraph 19. A communications device according to Paragraph 18, whereinthe parameter comprises at least one of a path loss, an error rate, areceived signal strength and a received signal quality.

Paragraph 20. A communications device according to any of Paragraphs 14to 19, wherein the first connection is a time division duplex connectionproviding uplink and downlink communications using the first carrierfrequency, and

-   -   the control circuitry is configured with the transmitter        circuitry and the receiver circuitry    -   to measure at least one of a signal strength and a signal        quality of signals received from the first infrastructure        equipment.

Paragraph 21. A communications device according to Paragraph 20, whereinthe control circuitry is configured with the receiver circuitry tomeasure at least one of the signal strength and the signal quality ofsignals representing an acknowledgement information in respect of thedata communicated from the communications device to the firstinfrastructure equipment using the first carrier frequency.

Paragraph 22. A communications device according to any of Paragraphs 14to 19, wherein the first connection is a frequency division duplexconnection providing downlink communications at a third carrierfrequency,

-   -   the signals received from the first infrastructure equipment        include acknowledgement information in respect of the data        communicated from the communications device to the first        infrastructure equipment using the first carrier frequency, and    -   the control circuitry is configured with the transmitter        circuitry and the receiver circuitry    -   to determine the attribute based on the received acknowledgement        information.

Paragraph 23. A communications device according to any of Paragraphs 14to 22, wherein a path loss associated with the communicating the datafrom the communications device to the first infrastructure equipmentusing the first carrier frequency data exceeds a path loss for thesignals received from the first infrastructure equipment.

Paragraph 24. A communications device according to Paragraph 23, whereina beamforming technique is applied by the first infrastructure equipmentto the signals received from the first infrastructure equipment.

Paragraph 25. A communications device method according to any ofParagraphs 14 to 24, wherein the first carrier frequency is greater than3 GHz.

Paragraph 26. A communications device method according to any ofParagraphs 14 to 25, wherein the second carrier frequency is less than 2GHz.

Paragraph 27. A method for receiving data by a first infrastructureequipment from a communications device in a wireless communicationsnetwork, the method comprising:

-   -   receiving the data transmitted by a communications device using        a first carrier frequency,    -   determining a parameter associated with the data transmitted by        the communications device to the first infrastructure equipment        using the first carrier frequency,    -   transmitting an indication of the determined parameter to one of        the communications device and a second infrastructure equipment        providing uplink resources for the communication of the data        using a second carrier frequency different from the first        carrier frequency, and    -   after the transmitting, receiving a fraction of uplink data        transmitted by the communications device, the remainder of the        data transmitted by the communications device being transmitted        to the second infrastructure equipment and the fraction being        determined by the communications device based on at least the        indication of the determined parameter.

Paragraph 28. A method according to Paragraph 27, comprising

-   -   receiving an indication of a load of the second infrastructure        equipment, and    -   transmitting a network parameter based on the indication of the        load of the second infrastructure equipment to the        communications device, wherein    -   the fraction is determined based on at least the network        parameter.

Paragraph 29. A method according to Paragraph 27 or Paragraph 28,comprising

-   -   determining the fraction,    -   allocating resources using the first carrier frequency based on        the fraction, and    -   transmitting an indication of the allocated uplink resources        using the first carrier frequency to the communications device.

Paragraph 30. A method according to any of Paragraphs 27, 28 or 29,comprising

-   -   receiving an indication from the second infrastructure equipment        of the uplink resources allocated for the communication of the        data by the communications device using a second carrier        frequency to the second infrastructure equipment, and    -   transmitting an indication of the allocated uplink resources        using the second carrier frequency to the communications device.

Paragraph 31. A method according to any of Paragraphs 27 to 30, whereinthe parameter comprises at least one of a path loss, an error rate, areceived signal strength and a received signal quality.

Paragraph 32. A method for receiving data from a wireless communicationsdevice the method comprising:

-   -   receiving from a first infrastructure equipment an indication of        an parameter associated with the data transmitted by the        communications device using a first carrier frequency to the        first infrastructure equipment,    -   allocating resources on a second carrier frequency different        from the first carrier frequency for a fraction of the data to        be transmitted by the communications device to a second        infrastructure equipment using the second carrier frequency,    -   transmitting an indication of the allocated resources to one of        the first infrastructure equipment and the communications        device, and    -   receiving a fraction of data transmitted by the communications        device using the second carrier frequency,    -   wherein the remainder of the data transmitted by the        communications device is transmitted to the first infrastructure        equipment using the first carrier frequency and the fraction is        determined based on the parameter and    -   the parameter comprises at least one of a path loss, an error        rate, a received signal strength and a received signal quality.

Paragraph 33. A method according to Paragraph 32 comprising

-   -   receiving from one of the first infrastructure equipment and the        communications device a request to establish a connection with        the communications device.

Paragraph 34. A method according to Paragraph 32 or Paragraph 33,comprising

-   -   determining the fraction based on the parameter and a load of        the second infrastructure equipment.

Paragraph 35. A wireless communications system comprising a firstinfrastructure equipment and a second infrastructure equipment and acommunications device,

-   -   the first infrastructure equipment and the second infrastructure        equipment forming part of a wireless communications network,    -   the communications device being configured to transmit a        fraction of data corresponding to a fraction to the first        infrastructure equipment using resources using a first carrier        frequency,    -   the communications device being configured to transmit the        remainder of the data to the second infrastructure equipment        using resources using a second carrier frequency,    -   the fraction being determined based on at least one of signals        transmitted by the first infrastructure equipment which are        received by the communications device, a load of the second        infrastructure equipment, an amount of available resources on        the second carrier frequency and measurements of signals        transmitted by the communications device which are received by        the first infrastructure equipment.

In so far as embodiments of the disclosure have been described as beingimplemented, at least in part, by software-controlled data processingapparatus, it will be appreciated that a non-transitory machine-readablemedium carrying such software, such as an optical disk, a magnetic disk,semiconductor memory or the like, is also considered to represent anembodiment of the present disclosure.

It will be appreciated that the above description for clarity hasdescribed embodiments with reference to different functional units,circuitry and/or processors. However, it will be apparent that anysuitable distribution of functionality between different functionalunits, circuitry and/or processors may be used without detracting fromthe embodiments.

Described embodiments may be implemented in any suitable form includinghardware, software, firmware or any combination of these. Describedembodiments may optionally be implemented at least partly as computersoftware running on one or more data processors and/or digital signalprocessors. The elements and components of any embodiment may bephysically, functionally and logically implemented in any suitable way.Indeed the functionality may be implemented in a single unit, in aplurality of units or as part of other functional units. As such, thedisclosed embodiments may be implemented in a single unit or may bephysically and functionally distributed between different units,circuitry and/or processors.

Although the present disclosure has been described in connection withsome embodiments, it is not intended to be limited to the specific formset forth herein. Additionally, although a feature may appear to bedescribed in connection with particular embodiments, one skilled in theart would recognize that various features of the described embodimentsmay be combined in any manner suitable to implement the technique.

REFERENCES

-   [1] RP-170847, “New WID on New Radio Access Technology,” NTT DOCOMO,    RAN #75-   [2] R1-165364, “Support for Beam Based Common Control Plane”, Nokia,    Alcatel-Lucent Shanghai Bell, RAN1 #85-   [3] R1-1711817, “WF on LTE/NR DC deployment scenarios to extend NR    UL coverage”, Orange, Deutsche Telekom, Ericsson, China Unicom,    OPPO, Huawei, China Telecom, Nokia, ZTE, RAN1 NR Ad-Hoc #2-   [4] LTE for UMTS: OFDMA and SC-FDMA Based Radio Access, Harris Holma    and Antti Toskala, Wiley 2009, ISBN 978-0-470-99401-6.

What is claimed is:
 1. A method for transmitting data by acommunications device in a wireless communications network, the methodcomprising: allocating a fraction of the data for transmitting to afirst infrastructure equipment of the wireless communications networkusing a first carrier frequency, allocating a remainder of the data fortransmitting to a second infrastructure equipment of the wirelesscommunications network different from the first infrastructure equipmentusing a second carrier frequency, the second carrier frequency differingfrom the first carrier frequency, transmitting the fraction of datausing the first carrier frequency and the remainder of data using thesecond carrier frequency, determining an attribute associated withcommunicating the data from the communications device to the firstinfrastructure equipment using the first carrier frequency includingmeasuring or estimating the attribute based upon acknowledgementinformation with respect to the data communicated from the communicationdevice to the first infrastructure equipment using the first carrierfrequency, the acknowledgement information being included in signalsreceived from the first infrastructure equipment, modifying the fractionbased on at least the determined attribute, and transmitting the datausing at least one of the first and second carrier frequencies accordingto the modified fraction.
 2. A method according to claim 1, the methodcomprising: establishing a first connection providing uplinkcommunications using one or more channels operating at the first carrierfrequency with the first infrastructure equipment, monitoring thedetermined attribute associated with communicating the data, in responseto the determined attribute satisfying predetermined conditions,requesting an establishment of a second connection for transmitting thedata, and receiving an allocation of resources using one or morechannels operating at the second carrier frequency for transmitting thedata to the second infrastructure equipment.
 3. A communications devicefor transmitting data in a wireless communications network, thecommunications device comprising: transmitter circuitry, receivercircuitry and control circuitry, wherein the control circuitry isconfigured to allocate a fraction of the data for transmitting to afirst infrastructure equipment of the wireless communications networkusing a first carrier frequency, to allocate a remainder of the data fortransmitting to a second infrastructure equipment of the wirelesscommunications network different from the first infrastructure equipmentusing a second carrier frequency, the second carrier frequency differingfrom the first carrier frequency, and to control the transmittercircuitry and the receiver circuitry to transmit the fraction of datausing the first carrier frequency and the remainder of data using thesecond carrier frequency, to determine an attribute associated withcommunicating the data from the communications device to the firstinfrastructure equipment using the first carrier frequency includingmeasuring or estimating the attribute based upon acknowledgementinformation with respect to the data communicated from the communicationdevice to the first infrastructure equipment using the first carrierfrequency, the acknowledgement information being included in signalsreceived from the first infrastructure equipment, to modify the fractionbased on at least the determined attribute, and to transmit the datausing at least one of the first and second carrier frequencies accordingto the modified fraction.
 4. A communications device according to claim3, wherein the control circuitry is configured with the transmittercircuitry and the receiver circuitry to establish a first connectionproviding uplink communications using one or more channels operating atthe first carrier frequency with the first infrastructure equipment, tomonitor the determined attribute associated with communicating the data,in response to the determined attribute satisfying predeterminedconditions, to request an establishment of a second connection fortransmitting the data, and to receive an allocation of resources usingone or more channels operating at the second carrier frequency fortransmitting the data to the second infrastructure equipment.
 5. Acommunications device according to claim 3, wherein the controlcircuitry is configured with the transmitter circuitry and the receivercircuitry to receive, from one of the first infrastructure equipment andthe second infrastructure equipment an indication of a networkparameter, and to modify the fraction based on a combination of thedetermined attribute and the received network parameter.
 6. Acommunications device according to claim 5, wherein the networkparameter is based on a load of the second infrastructure equipment. 7.A communications device according to claim 3, wherein the controlcircuitry is configured with the transmitter circuitry and the receivercircuitry to receive an indication of a parameter associated withcommunicating the data from the communications device using the firstcarrier frequency from the first infrastructure equipment, and todetermine the attribute based on the parameter.
 8. A communicationsdevice according to claim 7, wherein the parameter comprises at leastone of a path loss, an error rate, a received signal strength and areceived signal quality.
 9. A communications device according to claim3, wherein the first connection is a time division duplex connectionproviding uplink and downlink communications using the first carrierfrequency, and the control circuitry is configured with the transmittercircuitry and the receiver circuitry to measure at least one of a signalstrength and a signal quality of signals received from the firstinfrastructure equipment.
 10. A communications device according to claim9, wherein the control circuitry is configured with the receivercircuitry to measure at least one of the signal strength and the signalquality of signals representing an acknowledgement information inrespect of the data communicated from the communications device to thefirst infrastructure equipment using the first carrier frequency.
 11. Acommunications device according to claim 3, wherein the first connectionis a frequency division duplex connection providing downlinkcommunications at a third carrier frequency, the signals received fromthe first infrastructure equipment include acknowledgement informationin respect of the data communicated from the communications device tothe first infrastructure equipment using the first carrier frequency,and the control circuitry is configured with the transmitter circuitryand the receiver circuitry to determine the attribute based on thereceived acknowledgement information.
 12. A communications deviceaccording to claim 3, wherein a path loss associated with thecommunicating the data from the communications device to the firstinfrastructure equipment using the first carrier frequency data exceedsa path loss for the signals received from the first infrastructureequipment.
 13. A communications device according to claim 12, wherein abeamforming technique is applied by the first infrastructure equipmentto the signals received from the first infrastructure equipment.
 14. Acommunications device according to claim 3, wherein the first carrierfrequency is greater than 3 GHz.
 15. A communications device accordingto claim 3, wherein the second carrier frequency is less than 2 GHz. 16.A method for receiving data by a first infrastructure equipment from acommunications device in a wireless communications network, the methodcomprising: receiving the data transmitted by a communications deviceusing a first carrier frequency, determining a parameter associated withthe data transmitted by the communications device to the firstinfrastructure equipment using the first carrier frequency, transmittingacknowledgement information with respect to the data communicated fromthe communication device to the first infrastructure equipment to thecommunications device, and after the transmitting, receiving a fractionof uplink data transmitted by the communications device, the remainderof the data transmitted by the communications device being transmittedto a second infrastructure equipment providing uplink resources for thecommunication of the data using a second carrier frequency differentfrom the first carrier frequency and the fraction being determined bythe communications device including measuring or estimating the fractionbased on the acknowledgement information.
 17. A method according toclaim 16, comprising receiving an indication of a load of the secondinfrastructure equipment, and transmitting a network parameter based onthe indication of the load of the second infrastructure equipment to thecommunications device, wherein the fraction is determined based on atleast the network parameter.
 18. A method according to claim 16,comprising determining the fraction, allocating resources using thefirst carrier frequency based on the fraction, and transmitting anindication of the allocated uplink resources using the first carrierfrequency to the communications device.
 19. A method according to claim16, comprising receiving an indication from the second infrastructureequipment of the uplink resources allocated for the communication of thedata by the communications device using a second carrier frequency tothe second infrastructure equipment, and transmitting an indication ofthe allocated uplink resources using the second carrier frequency to thecommunications device.
 20. A method according to claim 16, wherein theparameter comprises at least one of a path loss, an error rate, areceived signal strength and a received signal quality.